Question

A balloon is rising vertically up with a velocity of 29 m$s^{-1}$. A stone is dropped from it and it reaches the ground in 10 seconds. The height of the balloon when the stone was dropped from it is (g=9.8 m$s^{-2}$)

• A. 100 m
• B. 200 m
• C. 400 m
• D. 150 m

Answer 1

The correct option is B 200 m

For stone to be dropped from rising balloon of velocity 29m/s.
u=-29 m/s, t=10 sec.

$\therefore$ h=-29$\times 10+\frac{1}{2}\times 9.8\times 100$
=-290+490=200m.